The idiots making those threats likely aren't smart enough to track anyone down. Who is going to go through the trouble of tracking someone down, even if they knew how, then travel to wherever this other person lives, identify them correctly and do bodily harm to them? All over a video game. The time, money and effort to do all of that is absolutely unrealistic. Besides, if some one is going to make threats like that you can report them to mutiple sources and they can face serious consequences for those threats.